Lizard928

Alright
87 5 Speed.

I dove into the pod today to try and find out what was up with the charge light as it wasnt coming on.
I found that the bulb is good and I have power to it. But no ground.
I am guessing that I have to go to the altenator for the next check?

I also am finding that once going in to the pod and unplugging and reconnecting things I found that when I put the key to the ON position that all the lights (except alt light) flash on then turn off immediately.
Is this possibly due to the altenator light not working?
It is possible that it was this way before going in there, I just never really looked.

The gas guage also tended to get connection then loose it. When I moved the connector on the drivers side of the instrument cluster it would go on and off.
So I decided to bend the tabs down abit in the plug to give it alittle more pressure on the contact point as I could see a few of them were splayed open pretty far.
Well then I did something abit silly. As I was bending the tabs. I had forgotten to turn off the key or I bumped it, one of the two. And the tool I was using managed to brush between a couple of wires, this was instantanious and split second. However something has been lightly buggered as when I put the key in the on position now the ! light in the center console is aluminated along with the turn signal light in the center of the cluster, but the ! in the cluster is not illuminated. If I press the ! button on the console then they all get alot dimmer.
I can also hear the turn signal relay buzzing away while this is happening. I pulled it and I loose the noise, but the lights act the same sans the turn signal light in the cluster.
Now the other funny thing is that when I start the car like this. It fires right up (better than normal actually) and runs perfectly, but I get no Tach or other things until I press the ! on the console. Then my tach comes on, reads alittle high though. As well as most of the other things come on.
Does anyone have any ideas as to what might have blown/created a ground short?
It is acting almost as if the cluster is getting no ground at all and it is pulling a ground through other things connected to the board.

TIA

Jim bailey - 928 International

You might want to get a spare plastic foil circuit board while they are still being made....the 78 is gone and 82-84 as well . I bought a new one for the very brown 1980 a few months ago (of course have not installed it since the old one still works) . It is just a matter of time until we order replacements and are told ...N L A ,no longer available. They cost about $100 when they go NLA they are just about ....priceless . I am not one to recommend buying a lot of parts that you MIGHT need someday I just know how many people with 82-84s have been calling to get used circuit boards and trying to make soldered repairs. Then they ask me " What do I do ?? "

Lizard928

Thanks Jim,

I already have one sitting in a box right beside me

though the part which was touched was not connected to the printed board when this happened.

Jim bailey - 928 International

Good deal , you have your back covered ! so to speak.

Alan

If there is a connection issue to the alternator this is the behaviour I would expect. Check the small terminal on the alternator and connectivity back to the exciter line (if you closed the pod back up - you can get to it on the CE panel as well).

Alan

Big AL in VA

Do you have the WSM schematics?
OK, I will assume you do.
Now you need to look at your schematics and find which device on the pod is clearly supposed to be a ground (brown wire). Once you find this and confirm, take a jumper and go from this pin or terminal to a clean metal surface on the car chasis. Whatever is convenient to you near the pod.
Touch this grounded jumper to the one side of the device that is supposed to be grounded. See if the problem gets better.
If it does but some dimness remains in some devices go to another point.
You are essentially going through a process of elimination to find the source of your problem.
If you have a short it gets a little harder. To find a short you need to start disconnecting Pod components one at a time to find out if the problem goes away or gets better.
Both processes are methodical in their approach.
Be very careful doing this. Shorting out pins or terminals could open up one of the traces on the PC board on the back of the POD. Make sure you have the correct size fuses installed.

Hope this helps. And good luck. I have been an Electrician/Electronics guy for over 20 years and work at the Washington Post. I have done my own Electrical work on my 928S2 Euro.

BIG AL in VA
84 928S2 Euro twin distributor monster

Lizard928

Alan, Thanks I have to get in there and check the connection at the altenator, I know. Will report back on that.

I do have the manuals though the wiring schematics are tricky at best. I have to admit that I was hoping someone already had been through this and may have a direction they can point me in.

heinrich

WHAT!??? The great Lizard, the only man in history to be known to have successfully installed a 32V engine and harness into an ob!!??? And he is asking US!!??? How the hell should we know if you don't Dude

Lizard928

I was hoping that someone may have run into something like this before.

I havent printed of the pages of the electrical diagrams to start looking through there to see where the problem would be.

SharkSkin

I've had this sort of thing happen on other cars. What exactly did you short to what? BTW if you ground the small wire to the alt (disconnect from alt and ground the wire that leads back to the dash) and the light comes on, the circuit is probably fine. There would have been melted plastic and a lot of smoke if you burned up the resistor.

Lizard928

I shorted 2 wires in the drivers side multi pin connector to the circuit board.

I have verified that the resistor is working correctly, so I know that is ok.

I will be under the car doing some tests tomorrow morning and hope to find the problem then.

Though I can do electrical problems, of all the issues, I dislike them the most.

I prefer fixing something that you can physically see is broken and know exactly where to look.

SharkSkin

I figured it was the plug from your initial description, I was just thinking that if you knew WHICH pins, maybe we could trace it back and see which devices may have been damaged.

Lizard928

Just figured I would put a closure on this thread.

The wires I must have brushed in the 3rd connector would have been a black and brown.

Due to the symptoms, I figured that a diode or something had blown in either say the central warning system or something similar, Or that or a wire or two had shorted out together causing odd electrical flow.

Well in this instance. Not the case.

If you have the same symptoms as I had listed in the first post.
Then the problem is that the 5 amp fuse at the fusebox spot #10 for the instrument cluster has died.

That is all.

I like easy fixes. But man this one did not seem like a fuse that had blown.

HTH someone in the future.

SharkSkin

Cool, glad it was easy.